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Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers
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Author:  koogar [ 18 Oct 2010, 10:05 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

Gio wrote:
koogar wrote:
Just wondering if i use a 556 IC (dual 555) i might be able to make a delayed off and on which breaks the relay connection before it shuts down the power

Interesting idea. Are you also getting a turn off thump?

Hi Gio

at the moment ive have nothing to thump as i havent built my NP-100v12 - 12AU7 amp yet hoping to gets some eagle time this week ,but from the comments better to solve it before it happens dont want to fry my 580 jubilees .I dont doubt the circuit will have a 1001 uses for other projects :P

any ideas on implementing it using a 556 Gio ?

when i thought about it earlier today i thought it will be going down the soft start/off switching route ?


Koogar

Author:  Gio [ 18 Oct 2010, 10:20 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

koogar wrote:
any ideas on implementing it using a 556 Gio ?

when i thought about it earlier today i thought it will be going down the soft start/off switching route ?

Not really, but I will be interested in the end result. 8-)

How were you thinking you would activate the turn off process?
Cheers

Author:  koogar [ 18 Oct 2010, 11:33 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

I will have to wind the key up in the back of my head Gio before i answer that :P :turtle:

i also thought as a work around for the time being a fancy switch that breaks the relay contacts before breaking the power , As the relay has to be powered to make the contacts to the HP socket.

anyway i have a PSU to finish for this amp before i think of such things so i better put the kettle on :coffee:

i was wondering what Kramme had rustled up as an anti thump off he was working on something :P

koogar

Author:  KrammeAcoustics [ 19 Oct 2010, 12:43 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

koogar wrote:
i was wondering what Kramme had rustled up as an anti thump off he was working on something :P

Hi koogar

I really hope you'll keep on trying to find a solution, to help this thread staying alive . ;)

After 100 cups of coffee :coffee: and a lot of thinking, experiments of mine, begins to run out in the sand. :soapbox: The only thing i could come up with, wants a standby power supply and i don't want a circuit, which uses power in standby ( why not ? = the delay circuit of mine are mounted in a batteryversus Rogers Gomez Amp ).

A simple and functional solution ( k.i.s.s ), two switches can be used to both output for loudspeakers and headphones. One for power and another for the output. Turn on = switch 1 and few sec. later, switch 2. Turn off = switch 2 first, followed by switch 1. :mrgreen: I've used this solution first time, for more than 20 years ago, to DIY amps. It's an easy solution, but it works ...without thumps.

Ill. of two switch solution.

Image

Author:  robot797 [ 23 Oct 2010, 04:30 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

guys i have a few ideas how to do that

pleas give me one ore 2 days to make an turn of delay

Author:  koogar [ 23 Oct 2010, 20:36 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

robot797 wrote:
guys i have a few ideas how to do that

pleas give me one ore 2 days to make an turn of delay

Hi Robot that would be great if its a simple implementation im rather busy on my Tube amp project at the mo :P

Koogar

Author:  robot797 [ 24 Oct 2010, 13:28 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

here it is

i hope it is okay

Image

Author:  noelmem1 [ 25 Oct 2010, 23:50 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

heres a simple mod , just put r1 low resistance example 180 ohms , put r2 value to discharge the cap fast but not heat up during operation mode.

noelm

Author:  noelmem1 [ 26 Oct 2010, 13:10 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

looking again at the first schematic , when the timer Cap is not charged , the full supply is applied to the base emitter of the first transistor, this will surely kill it .

Again im attaching a fairly simple improvement using NPNs . You can actually play around with the values Tr1 could be a 1W transistor , Tr2 a 100 to 200mW transistor. Current through Tr1 could be 1/10th the current in Tr2 . Tr2 current is the supply voltage divided by the coils resistance. Choose 0.5w D2 zener such that the ckt triggers at least when C1 is at 6v so a zener value around 4 volts will be fine. Choose R3 such that it can sustain the zener current and charges timing cap C1 . R1 should be a low resistance 180R to keep D1 in non conducting mode while the speaker is on , R2 starts at 1KR up and together with D1 they discharge the cap quickly so no turn off thump. The 12v supply could come from the tranny and halfwave rectified, filtered with 100 to 220uF cap.

noelm

Author:  KrammeAcoustics [ 01 Nov 2010, 16:52 ]
Post subject:  Re: Simple Turn On Delay Circuit (Relay) Amplifiers & Speakers

Hi noelmem1

Thank you, for participation. The mods you've made looks interesting. :wizard:

Have you tried this delay relay ...is it only theoretical or does it actually works in practice ?

Could you please add some values and componentnames to the schematics, for a functional delay relay ?

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